Substrate processing method, substrate processing apparatus, and semiconductor device manufacturing method

ABSTRACT

A method for a substrate processing apparatus having a substrate holding mechanism and a chemical solution dispensing/sucking mechanism including a chemical solution dispensing port for supplying a first chemical solution and a chemical solution suction port, includes placing the target substrate on the substrate holding mechanism, laying out an auxiliary plate at a periphery of the substrate such that the two main faces are substantially flush with each other, supplying a second chemical solution onto the main faces, dispensing the first solution from the dispensing port and sucking the first and second solutions through the suction port, with the dispensing and suction ports brought into contact with the second solution, and while dispensing the first solution from the dispensing port and sucking the first solution through the suction port, scanning the dispensing/sucking mechanism such that the dispensing and suction ports are opposed to the main face of the substrate.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is based upon and claims the benefit of priority fromprior Japanese Patent Applications No. 2004-118279, filed Apr. 13, 2004;and No. 2004-189928, filed Jun. 28, 2004, the entire contents of both ofwhich are incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a substrate processing method and asubstrate processing apparatus for processing a substrate with achemical solution, and a semiconductor device manufacturing method usingthe same.

2. Description of the Related Art

A wet process is extensively used for a substrate processing techniquein a process of manufacturing a semiconductor device or a liquid crystaldisplay. In particular, regarding a developing process to be carried outafter a photosensitive resin is photosensitized, a puddle technique hasbeen actively studied.

In a conventional puddle technique, a chemical solution is supplied ontoa substrate to be processed (target substrate) while the substrate isrotated. The chemical solution is supplied by a chemical solution supplypart laid out above the substrate. However, it is very difficult for thechemical solution supply part to make uniform a dispensing pressure ofthe chemical solution or a chemical supply quantity per unit area at acentral part and at a peripheral part of the substrate. Therefore, ithas been very difficult to obtain uniform developing precision in theplane of the substrate. A problem associated with such processingprecision exists similarly in a substrate processing method other thanthe developing process.

As developing advances, a dissolved product or a developing solutionwith a low concentration is generated as a byproduct of suchadvancement. In general, it is believed that a dissolved product or adeveloping solution with a low concentration inhibits dissolution of aphotosensitive thin film. The dissolved product or the like is generatedaccording to the pattern density in the substrate, and thus, isgenerated with a certain distribution on the substrate. Then, thedissolved product or the like is subject to a force such as acentrifugal force caused by substrate rotation, and moves on thesubstrate with non-uniformity. For such a reason as well, in theconventional puddle technique, it has been impossible to obtain uniformprocessing precision in the plane.

There is proposed a substrate processing method using a suction nozzlein order to generate the flow of a chemical solution in the course ofdeveloping. For example, in Jpn. Pat. Appln. KOKAI Publication No.2002-252167 by the present inventors, there is proposed a nozzlecomprising a chemical solution dispensing port and a chemical solutionsuction port and a substrate processing method using the nozzle.

The above substrate processing method is directed to a method forprocessing a substrate in the case where a developing solution is usedas a chemical solution; namely, while dispensing the developing solutionfrom a developing solution dispensing port, sucking the developingsolution from a developing solution suction port, and then, processingthe substrate while scanning the nozzle in proximity to the substrate.The above substrate processing method is one method of making a nozzleproximal to a substrate, and increasing the flow rate of a chemical onthe substrate, thereby achieving replacement of the chemical betweenpatterns, and then, reducing a pattern dimensional difference caused bya pattern density.

In a state in which the nozzle and the substrate are thus very proximalto each other, bubbles or the like exist between the nozzle and thesubstrate. Such bubbles cause the impairment of the uniformity of theflow of the chemical on the substrate. Specifically, the flow rate orthe like of the chemical becomes different depending on an upstream sideand a downstream side with respect to a position at which the bubblesexist. Therefore, there has been a demand for providing a substrateprocessing method and a substrate processing apparatus capable ofpreventing the non-uniformity of the flow of the chemical caused by thebubbles.

In addition, a wet process is used for a substrate processing techniquein the steps of manufacturing a semiconductor device or a liquid crystaldisplay. In particular, regarding the developing and etching processesafter a photosensitive resin has been photosensitized, a paddle methodor a spray method are actively discussed. In these methods, in general,the developing solution or etching solution has been supplied andprocessed on the substrate, and then, the substrate is rotated whilepure water is supplied during rinse processing, thereby removing aby-product caused at the time of developing (resist residue) or metallicor organic particles and the like which may exist on the substrate.However, the by-product or particles and the like are not completelyreduced, thus causing the impaired yield of photomasks or wafers.

As developing or etching advances, a dissolved product or a resistresidue is produced as a by-product thereof. The product and residuefloat in the solution existing on the substrate, and it is believed thatthere is a high probability that the dissolved product, resist residueand the like exist on the vicinity of the liquid solution surface. Inthe latest investigation, it is found that, when the liquid on thesubstrate becomes thin, and then, disappears, the dissolved product,resist residue and the like existing on the liquid solution surface orin the liquid solution adhere to the substrate surface, causing adefect.

In Jpn. Pat. Appln. KOKAI Publication No. 2002-252167 describedpreviously, there is proposed a nozzle which comprises a chemicalsolution dispensing port and a chemical solution sucking port and asubstrate processing method using the nozzle. The document describes acase of using a developing solution as a chemical solution and relatesto a method of sucking the developing solution from a developingsolution sucking port while dispensing the developing solution from adeveloping solution dispensing port, and then, processing the substratewhile carrying out scanning with the nozzle being proximal to thesubstrate. In more detail, by making the nozzle proximal to thesubstrate, the replacement of the chemical solution between patterns isachieved by increasing the flow rate of the chemical, and one method forreducing the pattern dimensional difference caused by a pattern densityis provided.

A sucking part exists at the above reported nozzle. The sucking sectioncarries out processing while sucking and removing particles such as thedissolved product or resist reside contained in the liquid solutionexisting on the substrate. Thus, there is an advantage that theseparticles can be almost removed from the top of the substrate. However,the monitoring of particles is not carried out, thus making it possibleto deny a possibility that a dissolved product or a floating object suchas a resist residue exists on a liquid surface.

Therefore, there is a growing demand for a technique for guaranteeingthat the particles hardly exist in the liquid before drying thesubstrate surface. That is, there has been a demand for achieving asubstrate processing method and a substrate processing apparatus capableof restricting the particles from adhering to the substrate surfaceafter drying the substrate surface and improving the yielding.

BRIEF SUMMARY OF THE INVENTION

According to a first aspect of the invention, there is provided a methodof substrate processing, which comprises:

preparing a substrate processing apparatus comprising a substrateholding mechanism to hold a target substrate to be processed having afirst main face, and a chemical solution dispensing/sucking mechanismwhich comprises a chemical solution dispensing port to dispense a firstchemical solution, and a chemical solution suction port to suck achemical solution including the first chemical solution;

placing the target substrate on the substrate holding mechanism so as toexpose the first main face;

preparing an auxiliary plate having a second main face, followed bylaying out the auxiliary plate at a periphery of the target substratesuch that the second main face is substantially flush with the firstmain face;

supplying a second chemical solution onto the first main face and thesecond main face;

dispensing the first chemical solution from the chemical solutiondispensing port and sucking the first chemical solution and the secondchemical solution through the chemical solution suction port, in a statein which the chemical solution dispensing port and the chemical solutionsuction port are brought into contact with the second chemical solution;and

while dispensing the first chemical solution from the chemical solutiondispensing port and sucking the first chemical solution through thechemical solution suction port, scanning the chemical solutiondispensing/sucking mechanism in a state in which the chemical solutiondispensing port and the chemical solution suction port are opposed tothe first main face of the target substrate.

According to a second aspect of the invention, there is provided anapparatus for substrate processing, which comprises:

a substrate holding mechanism to hold a target substrate to be processedhaving a first main face;

a chemical solution dispensing/sucking mechanism including a chemicalsolution dispensing port to dispense a first chemical solution onto thefirst main face and a chemical solution suction port to suck a chemicalsolution including the first chemical solution;

an auxiliary plate having a second main face, the auxiliary plate beinglaid out at a periphery of the target substrate such that the secondmain face is substantially flush with the first main face; and

at least one selected from the group consisting of (1) a recess portionprovided on the second main face of the auxiliary plate, the recessportion being wider than an area including the chemical solutiondispensing port and the chemical solution suction port, (2) adetermining mechanism to determine whether a bubble is present or absentin the chemical solution dispensing port; and (3) a vibration mechanismto vibrate the first chemical solution and the second chemical solution.

According to a third aspect of the invention, there is provided a methodof manufacturing a semiconductor device, which comprises:

preparing a substrate processing apparatus comprising a semiconductorwafer holding mechanism to hold a target semiconductor wafer to beprocessed having a first face and a chemical solution dispensing/suckingmechanism including a chemical solution dispensing port to dispense afirst chemical solution and a chemical solution suction port to suck achemical solution including the first chemical solution;

placing the target semiconductor wafer on the semiconductor waferholding mechanism so as to expose the first main face;

preparing an auxiliary plate having a second main face, followed bylaying out the auxiliary plate at the periphery of the targetsemiconductor wafer such that the second main face is substantiallyflush with the first main face;

supplying a second chemical solution onto the first main face and thesecond main face;

dispensing the first chemical solution from the chemical solutiondispensing port and sucking the first chemical solution and the secondchemical solution through the chemical solution suction port, in a statein which the chemical solution dispensing port and the chemical solutionsuction port are brought into contact with the second chemical solution,so as to preclude a first chemical solution from coming into contactwith the first main face of the target semiconductor wafer; and

while dispensing the first chemical solution from the chemical solutiondispensing port and sucking the first chemical solution through thechemical solution suction port, scanning the chemical solutiondispensing/sucking mechanism in a state in which the chemical solutiondispensing port and the chemical solution suction port are opposed tothe first main face of the target semiconductor wafer.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

FIG. 1 is a schematic sectional view showing an outline construction ofa substrate processing apparatus according to a first embodiment of theinvention;

FIG. 2 is a sectional view schematically depicting an outlineconstruction of a scan nozzle of the substrate processing apparatusaccording to the first embodiment;

FIGS. 3A to 3E are sectional views each illustrating a substrateprocessing method according to the first embodiment in a stepwisemanner;

FIGS. 4A to 4E are sectional views each illustrating a substrateprocessing method according to a second embodiment in a stepwise manner;

FIG. 5A is a sectional view showing a scan nozzle of a substrateprocessing apparatus according to a third embodiment of the invention;

FIG. 5B is a perspective view showing the scan nozzle of the substrateprocessing apparatus according to the third embodiment;

FIGS. 6A to 6F are sectional views each adopted to explain a substrateprocessing method according to the third embodiment;

FIGS. 7A to 7D are sectional views each adopted to explain an operationof developing solution dispensing, liquid suction, and rinse solutiondispensing according to a fourth embodiment of the invention;

FIG. 8 is a sectional view schematically depicting an outlineconstruction of a substrate processing apparatus according to a fifthembodiment;

FIG. 9 is a sectional view adopted to explain a modified example of thefifth embodiment;

FIG. 10 is a sectional view adopted to explain another modified exampleof the fifth embodiment;

FIG. 11 is a sectional view adopted to explain still another modifiedexample of the fifth embodiment;

FIG. 12 is a view showing an outline construction of a substrateprocessing part in a substrate developing device according to a sixthembodiment;

FIG. 13 is a sectional view showing a construction of an ozone waterdispensing/sucking head according to the sixth embodiment;

FIG. 14 is a bottom view showing the ozone water dispensing/sucking headin the developing device according to the sixth embodiment;

FIGS. 15 to 20 are bottom views showing a variety of layouts of chemicalsolution dispensing and suction ports according to the sixth embodiment;and

FIG. 21 is a schematic sectional view showing an outline construction ofa developing/cleaning device according to the sixth embodiment.

DETAILED DESCRIPTION OF THE INVENTION

Hereinafter, embodiments of the present invention will be described withreference to the accompanying drawings. According to the embodimentspresented below, there can be provided a substrate processing method anda substrate processing apparatus capable of preventing thenon-uniformity of flow of a chemical solution caused by air bubbles.

First Embodiment

FIG. 1 is a view schematically depicting an outline construction of asubstrate processing apparatus according to a first embodiment of thepresent invention. FIG. 2 is a view schematically depicting an outlineconstruction of a chemical solution dispensing/sucking mechanism of thesubstrate processing apparatus according to the present embodiment.

A substrate processing apparatus 100 comprises: a substrate holdingmechanism 10 for holding a target substrate 1 substantiallyhorizontally; an auxiliary plate 20 for surrounding the target substrate1 and the substrate holding mechanism 10 and making vertical movement; achemical solution dispensing/sucking mechanism 30 laid out above thesubstrate holding mechanism 10; and a chemical solution supply/suctionsystem for supplying a chemical solution or the like into the chemicalsolution dispensing/sucking mechanism 30 and sucking the chemicalsolution or the like from the inside of the chemical solutiondispensing/sucking mechanism 3.

The target substrate 1 comprises, for example, an Si wafer and aphotosensitive thin film provided on the Si wafer. The substrate holdingmechanism 10 is provided as a wafer holding device, for example. Anupper face of the auxiliary plate 20 is set to be substantially as highas, or slightly lower than an upper face of the target substrate 1 (forexample, an upper face of the photosensitive thin film).

The chemical solution dispensing/sucking mechanism 30, as shown in FIG.2, comprises a chemical solution dispensing/sucking head (hereinafter,referred to as a scan nozzle) 30SN. At the upper side of the scan nozzle30SN, there are provided: a chemical solution inlet 31 into which achemical solution 50 is to be introduced; first and second liquidoutlets 32 ₁, 32 ₂ which are laid out so as to sandwich the chemicalsolution inlet 31, the outlets causing a liquid solution 51 to bedischarged therefrom; and first and second rinse solution inlets 33 ₁,33 ₂ which are laid out at the outside of the liquid outlets 32 ₁, 32 ₂,the inlets causing a rinse solution 52 to be introduced therefrom. Thechemical 50 is provided as, for example, a developing solution. Theabove liquid solution includes, for example, a developing solution; purewater; a developing solution and pure water; a developing solution, purewater, and a rinse solution; or a developing solution and a rinsesolution.

On the other hand, at the lower side of the scan nozzle 30SN, there areprovided: a slit shaped chemical solution dispensing port 34 forsupplying the chemical solution 50 onto the target substrate 1; slitshaped first and second chemical solution suction ports 35 ₁, 35 ₂ whichare laid out at both sides of the chemical solution dispensing port 34,the suction ports being adopted to suck in the liquid 51 on the targetsubstrate 1; and first and second rinse solution dispensing port 36 ₁,36 ₂ which are laid out at the outside of the chemical solution suctionports 35 ₁, 35 ₂, the dispensing ports 36 ₁, 36 ₂ being adopted tosupply the rinse solution 52 onto the target substrate 1.

The chemical solution dispensing port 34 communicates with the chemicalsolution inlet 31 via a pipe 37. Similarly, the liquid solution outlets33 ₁, 33 ₂ and the rinse solution suction ports 35 ₁, 35 ₂ communicatewith each other via a pipe 38; and the rinse solution inlets 33 ₁, 33 ₂and the rinse solution dispensing ports 36 ₁, 36 ₂ communicate with eachother via a pipe 39. The pipes 37, 38, 39 each comprise a liquidsolution reservoir.

The chemical supply/suction system 40 comprises first and second liquidsolution suction systems 42 ₁, 42 ₂ and first and second rinse supplysystems 43 ₁, 43 ₂. The chemical supply system 41, the liquid solutionsuction systems 42 ₁, 42 ₂, and the rinse supply systems 43 ₁, 43 ₂ eachcommunicate with the chemical solution inlet 31, the liquid solutionoutlets 32 ₁, 32 ₂, and the rinse solution inlets 33 ₁, 33 ₂ via pipes44, 45 and 46. Valves 47, 48 and 49 are provided in the middle of thepipes 44, 45 and 46 each other.

By pressurizing a chemical solution canister (not shown), the chemicalsolution 50 is supplied into the pipe 45 via the chemical solution inlet31, and is dispensed from the chemical solution dispensing port 34. Theliquid solution suction systems 42 ₁, 42 ₂ are connected to the liquidsolution outlets 32 ₁, 32 ₂, respectively, via a pump (not shown). Theliquid solution is sucked in by a suction force of the pump. The rinsesolution is continuously dispensed from the rinse solution dispensingports 36 ₁, 36 ₂. In this case, a liquid solution including the chemicalsolution and the rinse solution is sucked into the liquid solutionsuction ports 35 ₁, 35 ₂.

A well known gap measuring mechanism and a gap adjusting mechanism,which are although not shown, are provided at the chemical solutiondispensing/sucking mechanism 30. The substrate processing apparatus 100further comprises a well known moving mechanism for relatively movingthe chemical solution dispensing/sucking mechanism 30 and the substrateholding mechanism 10.

FIGS. 3A and 3E are views each adopted to explain a substrate processingmethod using a substrate processing apparatus according to the presentembodiment. Here, a description will be given with respect to a casewhere the chemical liquid is a developing solution, namely, a case of adeveloping processing method. In the figures that follows FIG. 13A, thesubstrate holding mechanism 10 is omitted for clarity.

First, the target substrate 1 is prepared. The target substrate 1comprises: a semiconductor wafer; an undercoat film provided andprocessed on the wafer; and a resist pattern provided on the undercoatfilm. The resist pattern is produced as follows. That is, aphotosensitive resin film such as a resist having thickness of 0.4micron is formed on the undercoat film, and then, with an exposureprocess using a KrF excimer laser stepper, a 0.10 micron pattern latentimage is formed on the photosensitive resin film.

Next, the target substrate 1 is held horizontally by the substrateholding mechanism. Next, as shown in FIG. 3A, a liquid solution 51 (purewater at this stage) is filled on the target substrate 1 and theauxiliary plate 20 (first and second main faces) laid out so as tosurround the target substrate 1. The liquid solution 51 (second chemicalsolution) is supplied from a liquid solution filling nozzle 70. When theliquid solution 51 is filled, the liquid solution filling nozzle 70 ismoved from a liquid solution filling nozzle standby position (not shown)onto the target substrate 1. After the filling of the liquid solution 51has completed, the liquid solution filling nozzle 70 is moved from thetop of the target substrate 1 to the liquid solution filling nozzlestandby position.

Next, as shown in FIG. 3B, the scan nozzle 30SN is moved from a scannozzle standby position (not shown) upwardly of the auxiliary plate 20.Next, as shown in FIG. 3C, the scan nozzle 30SN moved to above theauxiliary plate 20 is fallen. Then, as shown in FIG. 3D, in a state inwhich a lower face (nozzle lower face) of the scan nozzle 30SN comesinto contact with a liquid level of the liquid solution 51, the scannozzle 30SN is held.

Here, at a moment at which the nozzle lower face has come into contactwith the liquid level of the liquid solution 51, air bubbles 80 enterthe inside of the chemical solution dispensing port 34 situated on thenozzle lower face. Therefore, in the present embodiment, in order toeliminate the air bubbles 80 from the inside of the chemical solutiondispensing port 34, operations of developing solution dispensing, liquidsolution sucking and rinse solution dispensing are made in a state inwhich the nozzle lower face has come into contact with the liquid levelof the liquid solution 51. By these operations, the air bubbles 80having entered the inside of the chemical solution dispensing port 34are purged out from the chemical solution dispensing port 34. The airbubbles 80 purged out from the chemical solution dispensing port 34 aresucked into the chemical solution suction ports 35 ₁, 35 ₂, and thesucked bubbles are purged out from the liquid solution outlets 32 ₁, 32₂ to the outside of the scan nozzle 30SN.

Similarly, at a moment at which the nozzle lower face has come intocontact with the liquid level of the liquid solution 51, air bubbles 80adhered to the nozzle lower face are released from the nozzle lower facedue to operations of developing solution dispensing, liquid solutionsucking and rinse solution dispensing. The air bubbles 80 released fromthe nozzle lower face are sucked into the chemical solution suctionports 35 ₁, 35 ₂, and the sucked bubbles are purged out from the liquidsolution outlets 32 ₁, 32 ₂ to the outside of the scan nozzle 30SN.

In order to reliably eliminate the air bubbles 80 having entered theinside of the chemical solution dispensing port 34 or the air bubbles 80adhered to the nozzle lower face, it is preferable to intermittentlycarry out operations of the above developing solution dispensing, liquidsolution sucking, and rinse solution dispensing.

It is desirable that a gap G1 between the nozzle lower face and theauxiliary plate 20 during operations of the developing solutiondispensing, liquid solution sucking and rinse solution dispensing isgreater than a diameter of each of the air bubbles 80 having entered thenozzle lower face. This is because, in the case where the gap G1 isequal to or greater than the diameter of the air bubbles 80, there is noneed for a large amount of force to move the air bubbles 80. Inactuality, it is considered desirable that the gap G1 is about 3 mmbecause the diameter of the air bubble 80 is about 0.1 mm to 3 mm ingeneral. In addition, during the operations of the above developingsolution dispensing, liquid solution sucking, and rinse solutiondispensing, it is preferable that the developing solution dispensed fromthe chemical solution dispensing port 34 should not come into contactwith the top of the target substrate 1. Further, it is preferable thatthe rinse solution dispensed from the rinse solution dispensing ports 36₁, 36 ₂ should not come into contact with the top of the targetsubstrate 1.

Next, as shown in FIG. 3E, the scan nozzle 30SN is further lowered untila gap G2 between the nozzle lower face and the auxiliary plate 20 isobtained as a desired value, i.e., 100 microns in the presentembodiment. Thereafter, while the gap G2 is held at the above desiredvalue, the operations of developing solution dispensing, liquid solutionsucking, and rinse solution dispensing are carried out, and the scannozzle 30SN is scanned above the target substrate 1 at a speed of 1 mmper second, thereby carrying out a developing process. At this time, thescan nozzle 30SN is scanned in a state in which the chemical solutiondispensing port 34, the chemical solution suction ports 35 ₁, 35 ₂ andthe rinse solution dispensing ports 36 ₁, 36 ₂ are opposed to an upperface of the target substrate 1.

In the present embodiment, tetramethyl ammonium hydroxide (TMAH)(normality 0.27N) is used as a developing solution. Further, adispensing flow rate of the developing solution, a suction flow rate ofliquid solution, and a suction pressure of the liquid solution suctionflow rate are adjusted in advance such that the developing solutiondispensed from the chemical solution dispensing port 34 is sucked intothe chemical solution suction ports 35 ₁, 35 ₂. Next, the targetsubstrate 1 is rotated, and the liquid solution on the target substrate1 is vibrated. Then, the target substrate 1 is dried, whereby a resistpattern forming process completes.

When the in-plane uniformity of a resist pattern formed in accordancewith the method of the embodiment was measured, a result of 2.7 nm (3σ)was obtained. On the other hand, when the in-plane uniformity of theresist pattern formed in accordance with the conventional technique(developing without elimination of air bubbles 80) was measured, aresult of 7.5 nm (3σ) was obtained. From the above results, it wasverified that a resist pattern having significantly improved uniformitycan be provided according to the embodiment.

After the scan nozzle 30SN had been fabricated of a transparent elementmaterial, when the presence of air bubbles or foreign objects (dustand/or particles) in the chemical solution dispensing port 34 and thepresence of air bubbles or foreign objects adhered to the nozzle lowerface were monitored, it was successfully verified that the number of airbubbles and foreign objects can be reduced to 0 by using the embodiment.

As has been described above, according to the present embodiment, thedispensing and sucking of the processing liquid solution (chemicalsolution, rinse solution) are carried out while a gap greater than thediameter of air bubble 80 is maintained on the auxiliary substrate 20laid out at the periphery of the target substrate 1. This makes itpossible to eliminate (bubble-remove) the air bubbles or foreign objectswhich exist in the chemical solution dispensing port 34 and the airbubbles or foreign objects adhered to the nozzle lower face by means ofsucking operation.

In the present embodiment, a bubble removing process is carried outwhile the nozzle lower face comes into contact with a liquid level abovethe auxiliary plate 20. In this manner, the bubble removing process canbe carried out while avoiding the outflow of the processing liquidsolution onto the target substrate 1 before substrate processing. Afterthe bubble removing process has completed, the scan nozzle 30SN is movedupwardly of the target substrate 1 in a state in which the nozzle comesinto contact with the liquid level, and substrate processing is carriedout. Accordingly, there is little possibility of new entry of airbubbles or the like.

Second Embodiment

FIG. 4 is a view adopted to explain a substrate processing method usinga substrate processing apparatus according to a second embodiment of theinvention. Here, a description will be given with respect to a casewhere a chemical solution is a developing solution, namely, a case of adeveloping processing method. Like constituent elements in FIGS. 1 to 3Eare designated by like reference numerals, and a detailed description isomitted here. In the following figures, like constituent elements in theexisting figures are designated by like reference numerals, and adetailed description is omitted here.

A substrate processing apparatus according to this embodiment isdifferent from that of the first embodiment in that the auxiliary plate20 comprises a recess portion 21 which is greater by one round than anarea in which there exist the chemical solution dispensing port 34, theliquid solution suction ports 35 ₁, 35 ₂ and the rinse solutiondispensing port 36 ₁, 36 ₂. In the embodiment, the depth of the recessportion 21 is 5 nm. In addition, a substrate processing method accordingto the present embodiment is different from that of the first embodimentin that air bubbles are eliminated in the recess portion 21.Hereinafter, the present embodiment will be described in detail.

First, as in the first embodiment, the target substrate 1 comprising awafer, an undercoat film, and a resist pattern is prepared. Then, thetarget substrate 1 is held horizontally by the substrate holdingmechanism.

Next, as shown in FIG. 4A, as in the first embodiment, the liquidsolution 51 is filled on the target substrate 1 and the auxiliary plate20 laid out so as to surround the target substrate 1.

Next, as shown in FIG. 4B, the scan nozzle 30SN is moved from a nozzlestandby position (not shown) upwardly of the auxiliary plate 20. At thistime, when seen from the top of the scan nozzle 30SN, the position ofthe scan nozzle 30SN is set at a position such that a region in whichthere exist the chemical solution dispensing port 34, the liquidsolution suction ports 35 ₁, 35 ₂ and the rinse solution dispensingports 36 ₁, 36 ₂ is included in the recess portion 21 provided on thesurface of the auxiliary plate 20.

Next, as shown in FIG. 4C, the scan nozzle 30SN moved onto the auxiliaryplate 20 is fallen. Then, as shown in FIG. 4D, the scan nozzle 30SN isheld in a state in which the nozzle lower face comes into contact withthe liquid level of the liquid solution 51. At this time, a gap G3between the nozzle lower face and the auxiliary plate 20 issubstantially equal to the gap G2 in the first embodiment.

Here, at a moment at which the nozzle lower face has come into contactwith the liquid level of the liquid solution 51, air bubbles 80 entersthe inside of the chemical solution dispensing port 34 situated on thenozzle lower face. Then, in the embodiment, in order to eliminate theair bubbles 80 from the inside of the chemical solution dispensing port34, operations of developing solution dispensing, liquid solutionsucking, and rinse solution dispensing are carried out in a state inwhich the nozzle lower face has come into contact with the liquid levelof the liquid solution 51. By these operations, the air bubbles 80having entered the inside of the chemical solution dispensing port 34are purged out from the chemical solution dispensing port 34. The airbubbles 80 purged out from the chemical solution dispensing port 34 aresucked into the chemical solution suction ports 35 ₁, 35 ₂, and then,the sucked air bubbles are purged out from the liquid solution outlets32 ₁, 32 ₂ to the outside of the scan nozzle 30SN.

Similarly, at a moment at which the nozzle lower face has come intocontact with the liquid level of the liquid solution 51, the air bubbles80 adhered to the nozzle lower face are also released from the nozzlelower face by the above operations of developing solution dispensing,liquid solution sucking, and rinse solution dispensing. Then, the airbubbles 80 released from the nozzle lower face are sucked into thechemical solution suction ports 35 ₁, 35 ₂, and the sucked air bubblesare purged out from the liquid solution outlets 32 ₁, 32 ₂ to theoutside of the scan nozzle 30SN.

In order to reliably eliminate the air bubbles 80 having entered theinside of the chemical solution dispensing port 34 or the air bubbles 80adhered to the nozzle lower face, it is preferable to intermittentlycarry out the above operations of developing solution dispensing, liquidsolution sucking, and rinse solution dispensing.

Next, as shown in FIG. 4E, the operations of developing solutiondispensing, liquid solution sucking, and rinse liquid solutiondispensing are carried out without changing the gap G3 (=G2) between thenozzle lower face and the auxiliary plate 20, and the scan nozzle 30SNis scanned above the target substrate 1 at a speed of 1 mm per second,thereby carrying out a developing process.

In this embodiment, TMAH (normality 0.27N) is used as a developingsolution. Further, a dispensing flow rate of the developing solution, asuction flow rate of liquid solution, and a suction pressure of theliquid solution suction flow rate are adjusted in advance such that thedeveloping solution dispensed from the chemical solution dispensing port34 is sucked into the chemical solution suction ports 35 ₁, 35 ₂. Next,the target substrate 1 is rotated, and the liquid solution on the targetsubstrate 1 is vibrated. Then, the target substrate 1 is dried, wherebya resist pattern forming process completes.

When the in-plane uniformity of a resist pattern formed in accordancewith the method of the embodiment was measured, a result of 2.7 nm (3σ)was obtained. On the other hand, when the in-plane uniformity of theresist pattern formed in accordance with the conventional technique(developing without elimination of air bubbles 80) was measured, aresult of 7.5 nm (3σ) was obtained. From the above results, it wasverified that a resist pattern having significantly improved uniformitycan be provided according to the embodiment.

When the scan nozzle 30SN was fabricated of a transparent elementmaterial, and the presence of air bubbles or foreign objects (dustand/or particles) in the chemical solution dispensing port 34 and thepresence of air bubbles or foreign objects adhered to the nozzle lowerface were monitored, it was successfully verified that the number of airbubbles and foreign objects can be reduced to 0 by using the presentembodiment.

Also in this embodiment, advantageous effect similar to that of thefirst embodiment can be attained. Further, according to the embodiment,in a state in which a region in which there exist the chemical solutiondispensing port 34, the liquid solution suction ports 35 ₁, 35 ₂, andthe rinse solution dispensing ports 36 ₁, 36 ₂ is included in the recessportion 21 of the auxiliary plate 20 when seen from the top, thedispensing and sucking of the processing liquid solution (nozzleoperation) are carried out, thereby making it possible to carry out abubble removing process more efficiently. In addition, there is anotheradvantageous effect that the number of recipes for carrying out nozzleoperation is reduced, and the bubble removing process can be easilycarried out.

In order to improve the advantageous effect of the present embodiment,an auto cleaning machine and/or a liquid solution removing mechanismetc. may be used to prevent a foreign object or the like from beingaccumulated in the recess portion 21.

Third Embodiment

FIGS. 5A and 5B are views each showing a scan nozzle of a substrateprocessing apparatus according to a third embodiment of the invention.FIG. 5A is a view schematically showing an outline construction of thescan nozzle, and FIG. 5B is a perspective view of the scan nozzle.

The substrate processing apparatus according to the embodiment isdifferent from that of the first embodiment in that the scan nozzle 30SNcomprises a light source 11 and a light receiving part 12 (lightreceiving element). The light source 11 comprises, for example, a laser.The light receiving part 12 comprises, for example, a photo diode.

The light source 11 is provided at one end of a slit shaped chemicalsolution dispensing port 34, and the light receiving part 12 is providedat the other end of the chemical solution dispensing port 34. An opticalaxis alignment is obtained such that the light emitted from the lightsource 11 transmits the chemical solution dispensing port 34 and isreceived by the light receiving part 12.

An optical system including the light source 11 and the light receivingpart 12 may not always be directly mounted on the scan nozzle 30SN. Theoptical system may be mounted on a device other than the scan nozzle30SN as long as the light beams radiated from the light source 11propagate so as to transmit the chemical solution dispensing port 34 andthe light receiving part 12 can measure the transmitted light quantity,a scattered light quantity, a reflection light quantity, or the like.

FIGS. 6A to 6F are views each adopted to explain a substrate processingmethod using the substrate processing apparatus of the embodiment. Here,a description will be given with respect to a case in which a chemicalsolution is a developing solution, namely, a case of a developingprocessing method.

First, the target substrate 1 is prepared. The target substrate 1comprises: a wafer; an undercoat film provided and processed on thewafer; and a resist pattern provided on the undercoat film. The resistpattern is produced as follows. That is, a photosensitive resin filmsuch as a resist having thickness of 0.3 micron is formed on theundercoat layer. Then, in accordance with an exposure process using anArF excimer stepper, a 0.07 micron pattern latent image is formed on thephotosensitive resin film.

Next, the target substrate 1 is held horizontally by the substrateholding mechanism 10. Next, as shown in FIG. 6A, the liquid solution 51(pure water at this stage) is filled on the target substrate 1 and theauxiliary plate 20 laid out so as to surround the target substrate 1.

Subsequently, as shown in FIG. 6B, the scan nozzle 30SN is moved from ascan nozzle standby position (not shown) upwardly of an auxiliary plate20. Next, as shown in FIG. 6C, the scan nozzle moved onto the auxiliaryplate 20 is fallen. Then, as shown in FIG. 6D, the scan nozzle 30SN isheld in a state in which a lower face (nozzle lower face) of the scannozzle 30SN has come into contact with the liquid level of the liquidsolution 51. At this time, a gap G1 between the nozzle lower face andthe auxiliary plate 20 is set to, for example, 3 mm.

Here, at a moment at which the nozzle lower face has come into contactwith the liquid level of the liquid solution 51, air bubbles 80 enterthe inside of the chemical solution dispensing port 34 situated on thenozzle lower face. Therefore, in the embodiment, in order to eliminatethe air bubbles 80 from the inside of the chemical solution dispensingport 34, operations of developing solution dispensing, liquid solutionsucking and rinse solution dispensing are made in a state in which thenozzle lower face has come into contact with the liquid level of theliquid solution 51. By these operations, the air bubbles 80 havingentered the inside of the chemical solution dispensing port 34 arepurged out from the chemical solution dispensing port 34. The airbubbles 80 purged out from the chemical solution dispensing port 34 aresucked into the chemical solution suction ports 35 ₁, 35 ₂, and thesucked bubbles are purged out from the liquid solution outlets 32 ₁, 32₂ to the outside of the scan nozzle 30SN.

Similarly, at a moment at which the nozzle lower face has come intocontact with the liquid level of the liquid solution 51, the air bubbles80 adhered to the nozzle lower face are also released by the aboveoperations of developing solution dispensing, liquid solution sucking,and rinse solution dispensing. Then, the air bubbles 80 released fromthe nozzle lower face are sucked into the chemical solution suctionports 35 ₁, 35 ₂, and the sucked air bubbles are purged out from theliquid solution outlets 32 ₁, 32 ₂ to the outside of the scan nozzle30SN.

Next, the above-described operations of developing solution dispensing,liquid solution sucking, and rinse solution dispensing are terminated,and then, light is radiated from the light source 11 provided at one endof the chemical solution dispensing port 34. The light radiated from thelight source 11 propagates the inside of the chemical solutiondispensing port 34 in its longitudinal direction. The propagated lightis received by the light receiving part 12 provided at the other end ofthe chemical solution dispensing port 34. The light receiving part 12outputs a current which corresponds to the received light quantity. Thiscurrent is measured by a measuring instrument (not shown). Themeasurement result is sent to a scan nozzle control part (not shown).

In the embodiment, the above light quantity was 1200 (arbitrary unit(a.u.)). On the other hand, a light quantity (reference value) which hadbeen measured in advance was 1240 (a.u.), which is the light quantity ofthe light received by the light receiving part 12, the light beingradiated from the light source 11 in a state in which no air bubbleswere included in the chemical solution dispensing port 34 and the insideof the dispensing port was filled with the developing solution. Thelight quantity (1240 (a.u.)) is stored as a reference value in advancein a scan nozzle control part (not shown).

In the embodiment, after the above-described operations of developingsolution dispensing, liquid solution sucking, and rinse solutiondispensing have been completed, the light quantity of the light receivedat the light receiving part 12 and the light quantity defined as areference value are compared with each other by the scan nozzle controlpart. As a result of the comparison, in the case where the values ofthese light quantities are equal to each other, processing goes to thestep shown in FIG. 6E. On the other hand, in the case where they are notequal, the above-described operations of developing solution dispensing,liquid solution sucking, and rinse solution dispensing are carried outagain. That is, the operations of developing solution dispensing, liquidsolution sucking, and rinse solution dispensing are repeated until ithas been determined that no air bubbles exist in the chemical solutiondispensing port 34.

In the case where it has been determined that no air bubbles exist inthe chemical solution dispensing port 34, as shown in FIG. 6E, the scannozzle 30SN is further fallen until a gap G2 between the nozzle lowerface and the auxiliary plate 20 has been set at a desired value, 50microns in this embodiment. Then, while the gap G2 is held at the abovedesired value, the operations of developing solution dispensing, liquidsolution sucking, and rinse solution dispensing are carried out, and thescan nozzle 30SN is scanned above the target substrate 1 at a speed of 1mm per second, thereby carrying out a developing process.

In the present embodiment, TMAH (normality 0.27N) is used as adeveloping solution. Further, a dispensing flow rate of the developingsolution, a suction flow rate of liquid solution, and a suction pressureof the liquid solution suction flow rate are adjusted in advance suchthat the developing solution dispensed from the chemical solutiondispensing port 34 is sucked into the chemical solution suction ports 35₁, 35 ₂.

Next, the target substrate 1 is rotated, and the liquid solution on thetarget substrate 1 is vibrated. Then, the target substrate 1 is dried,whereby a resist pattern forming process completes.

When the in-plane uniformity of a resist pattern formed in accordancewith the method of the embodiment was measured, a result of 2.7 nm (3σ)was obtained On the other hand, when the in-plane uniformity of theresist pattern formed in accordance with the conventional technique(developing without elimination of air bubbles 80) was measured, aresult of 7.5 nm (3σ) was obtained. From the above results, it wasverified that a resist pattern having significantly improved uniformitycan be provided according to the embodiment.

According to the present embodiment, advantageous effect similar to thataccording to the first embodiment can be attained. Further, according tothe embodiment, there can be provided advantageous effect that adeveloping process can be carried out after it has been verified that noair bubbles exist in the chemical solution dispensing port 34 by usingthe scan nozzle 30SN comprising the light source 11 and the lightreceiving part 12. That is, according to the present embodiment, thedeveloping process can be carried out in a state in which no air bubblesreliably exist in the chemical solution dispensing port 34, therebymaking it possible to reliably prevent the non-uniformity of the flow ofthe chemical solution caused by the air bubbles.

In the embodiment, although the auxiliary plate 20 according to thefirst embodiment has been used, the auxiliary plate 20 according to thesecond embodiment, namely, the auxiliary plate 20 comprising the recessportion 21 may be used. In this case, the bubble removing process iscarried out in the same manner as that in the second embodiment except aprocess for determining the presence or absence of air bubbles in thechemical solution dispensing port 34. The sensitivity adjustment of theoptical system including the light source 11 and the light receivingpart 12 is periodically carried out.

Fourth Embodiment

FIGS. 7A to 7D are views each adopted to explain a substrate processingmethod according to a fourth embodiment of the invention. In moredetail, these figures are views each adopted to explain a method formaking operations of developing solution dispensing, liquid solutionsucking, and rinse solution dispensing in the third embodiment.

First, as in the third embodiment, up to the processes shown in FIG. 6Care carried out. Next, the scan nozzle 30SN is held in a state in whicha lower face (nozzle lower face) of the scan nozzle 30SN has come intocontact with the liquid level of the liquid solution 51.

Here, at a moment at which the nozzle lower face has come into contactwith the liquid level of the liquid solution 51, air bubbles 80 enterthe inside of the chemical solution dispensing port 34 situated on thenozzle lower face. Then, in the embodiment, in order to eliminate theair bubbles 80 from the inside of the chemical solution dispensing port34, operations of developing solution dispensing, liquid solutionsucking, and rinse solution dispensing (dispensing/sucking operations)are carried out in a state in which the nozzle lower face has come intocontact with the liquid level of the liquid solution 51, as shown inFIGS. 7A to 7D. Here, these operations will be described in more detail.

First, as shown in FIG. 7A, dispensing/sucking operation is carried outfor 5 seconds in all the chemical solution dispensing port 34, thechemical solution suction ports 35 ₁, 35 ₂ and the rinse solutiondispensing ports 36 ₁, 36 ₂.

At this time, in the case where air bubbles have existed immediatelybeneath the chemical solution dispensing port 34, the air bubbles aresucked from the chemical solution suction ports 35 ₁, 35 ₂ with asubstantially equal suction force. Thus, the above air bubbles cannot besometimes removed while the bubbles are kept at their same position.

Next, as shown in FIG. 7B, dispensing/sucking operation is furthercarried out for 5 second in all the ports excluding the chemicalsolution suction port 35 ₁. At this time, in the case where air bubbleshave existed immediately beneath the chemical solution suction port 34,the sucking by the chemical solution suction port 35 ₁ stops. Thus, theabove air bubbles are sucked by the inside of the chemical solutionsuction port 35 ₂, and the sucked bubbles are removed.

Next, as shown in FIG. 7C, dispensing/sucking operation is furthercarried out for 5 seconds in all the ports excluding the chemicalsolution suction port 35 ₂. At this time, in the case where air bubbleshave existed immediately beneath the chemical solution suction port 34,the sucking by the chemical solution suction port 35 ₂ stops. Thus, theresidual air bubbles are sucked into the chemical solution suction port35 ₁, and the sucked bubbles are removed.

Next, as in the third embodiment, light is radiated from the lightsource 11 provided at one end of the chemical solution dispensing port34. The light is received at the light receiving part 12 provided at oneend of the chemical solution dispensing port 34. Further, the lightquantity of the received light and the light quantity 1240 (a.u.)defined as a reference value are compared with each other. In thisembodiment, the light quantity of the received light was 1150 (a.u.).

Then, as shown in FIG. 7D, dispensing/sucking operation was carried outfor 5 seconds in all the ports of the chemical solution dispensing port34, the chemical solution suction ports 35 ₁, 35 ₂, and the rinsesolution dispensing ports 36 ₁, 36 ₂. Then, light was radiated from thelight source 11, the light was received at the light receiving port 12,and then, the light quantity was measured.

As a result, the light quantity was 1240 (a.u.) which is equal to areference value. That is, it was determined that no air bubbles exist inthe chemical solution suction port 35 ₂. The dispensing/suckingoperation shown in FIGS. 7A to 7C may be carried out instead of thedispensing/sucking operation shown in FIG. 7D. The dispensing/suckingoperation according to the present embodiment is repeated until it hasbeen determined that no air bubbles exist in the chemical solutionsuction port 35 ₂.

Then, a process (FIGS. 6E and 6F) which is similar to that according tothe third embodiment is carried out, and a developing processterminates.

When the in-plane non-uniformity of the resist pattern formed inaccordance with the method of the embodiment was measured, a result of2.7 nm (3σ) was obtained. On the other hand, when the in-planeuniformity of the resist pattern formed in accordance with theconventional technique (developing without elimination of air bubbles80) was measured, a result of 7.5 nm (3σ) was obtained. From the aboveresults, it was verified that a resist pattern having significantlyimproved uniformity can be provided according to the embodiment.

According to the embodiment, advantageous effect similar to thataccording to the third embodiment can be attained. Further, according tothe embodiment, dispensing/sucking operation is carried out such thatair bubbles hardly remain in the chemical solution dispensing port 34,thus making it possible to more effectively prevent the non-uniformityof the flow of the chemical solution caused by the air bubbles.

The dispensing/sucking operation according to the present embodiment canbe applied to the first embodiment, the second embodiment, and further,a fifth embodiment described later. Furthermore, this operation can beapplied to a substrate processing apparatus and a substrate processingmethod which do not use an auxiliary plate.

In addition, a combination example of dispensing/sucking operation isnot limited to that of the embodiment. Various modifications can occurdepending on the number of dispensing ports, the number of suctionports, or their arrangement sequences, of the scan nozzle 30N. That is,any construction may be provided as long as it can change the pressureor flow of a liquid solution in the left and right regions whichsandwich the suction port in order to remove the air bubbles in thedispensing port.

Fifth Embodiment

FIG. 8 is a view schematically depicting an outline construction of asubstrate processing apparatus according to a fifth embodiment of theinvention. The substrate processing apparatus according to thisembodiment is different from that of the third embodiment in that avibrator 13 is incorporated in the scan nozzle 30SN.

The vibrator 13 can be vibrated by selecting any arbitrary one of aplurality of vibration frequencies. The above vibration frequency is notlimited in particular as long as it does not affect pattern dimensionsin the target substrate 1.

Now, a description will be given with respect to a substrate processingmethod using the substrate processing apparatus of the embodiment. Here,a description will be given with respect to a case where the chemicalliquid is a developing solution, namely, a case of a developingprocessing method.

First, as in the third embodiment, the liquid solution 51 is filled onthe target substrate 1 and the auxiliary plate 20 laid out so as tosurround the target substrate 1. Next, the scan nozzle 30SN is movedfrom a scan nozzle standby position (not shown) upwardly of theauxiliary plate 20. Then, the scan nozzle 30SN is fallen, and the scannozzle 30SN is held in a state in which the nozzle lower face has comeinto contact with the liquid level of the liquid solution 51. At thistime, a gap G1 between the nozzle lower face and the auxiliary plate 20is set to, for example, 4 mm.

Here, at a moment at which the nozzle lower face has come into contactwith the liquid level of the liquid solution 51, air bubbles 80 enterthe inside of the chemical solution dispensing port 34 situated on thenozzle lower face. Therefore, in the present embodiment, in order toremove the air bubbles 80 from the inside of the chemical solutiondispensing port 34, operations of developing solution dispensing, liquidsolution sucking, and rinse solution dispensing (dispensing/suctionoperations) are carried out in a state in which the nozzle lower facehas come into contact with the liquid level of the liquid solution 51and the vibrator 13 is operated to vibrate the scan nozzle 31. In moredetail, the dispensing/sucking operation is carried out for 5 second andfive times for all the ports of the chemical solution dispensing port34, the chemical solution suction ports 35 ₁, 35 ₂, and the rinsesolution dispensing ports 36 ₁, 36 ₂.

Next, light is radiated from the light source 11 provided at one end ofthe chemical solution dispensing port 34. Then, the light is received atthe light receiving section 12 provided at one end of the chemicalsolution dispensing port 34. Further, the light quantity of the receivedlight and the light quantity 1240 (a.u.) defined as a reference valueare compared with each other. In the embodiment, the light quantity ofthe received light was 1240 (a.u). That is, it was determined that noair bubbles exist in the chemical solution dispensing port 35 ₂.

Next, the scan nozzle 30SN is further lowered until a gap between thenozzle lower face and the auxiliary plate 20 is obtained as a desiredvalue, i.e., 100 microns in the present embodiment. Thereafter, whilethe gap is held at the above desired value, the operations of developingsolution dispensing, liquid solution sucking, and rinse solutiondispensing are carried out, and the scan nozzle 30SN is scanned abovethe target substrate 1 at a speed of 3 mm per second, thereby carryingout a developing process.

Next, the target substrate 1 is rotated, and the liquid solution on thetarget substrate is vibrated. Then, the target substrate 1 is dried,whereby a process for forming a resist pattern completes.

When the in-plane uniformity of a resist pattern formed in accordancewith the method of the embodiment was measured, a result of 2.7 nm (3σ)was obtained. On the other hand, when the in-plane uniformity of theresist pattern formed in accordance with the conventional technique(developing without elimination of air bubbles 80) was measured, aresult of 7.5 nm (3σ) was obtained. From the above results, it wasverified that a resist pattern having significantly improved uniformitycan be provided according to the embodiment.

According to the embodiment, advantageous effect similar to thataccording to the third embodiment can be attained. Further, according tothe embodiment, the scan nozzle 30SN is vibrated by the vibrator 13during dispensing/sucking operation. In this manner, the air bubbles inthe chemical solution dispensing port 34 can be effectively moved, thusmaking it possible to more effectively remove the air bubbles.

In addition, the substrate processing apparatus and the substrateprocessing method using the vibrator according to the embodiment can beapplied to any of the first, second, and fourth embodiments.

FIGS. 9 to 11 each show an modified embodiment of the presentembodiment. FIG. 9 shows an embodiment of using an arm 14 capable ofvertically vibrating the scan nozzle 30SN in a state in which the scannozzle 30SN is held instead of the vibrator 13.

FIG. 10 shows a modified embodiment of using a vibration mechanism 15which applies vibration (including pulsation) to the chemical solutionintroduced into the chemical solution inlet 31, thereby making it easyto move the air bubbles in the chemical solution inlet 31.

FIG. 11 shows a modified embodiment of using the vibration mechanism 15which applies vibration (including pulsation) to the liquid dischargedfrom the liquid solution exits 32 ₁, 32 ₂ instead of the vibrator 13,thereby making it easy to move the air bubbles in the chemical solutioninlet 31.

The above modified examples shown in FIGS. 9 to 11 can also be appliedto any of the first, second and fourth embodiments.

The present invention is not limited to the above-described embodiments.For example, while the above embodiments have described a case ofapplying the present invention to developing of a resist on a wafer, thepresent invention can also be applied to, for example, wet etching of afilm (insulation film, electrically conducting film) on a wafer;developing of a photosensitive film on a substrate in a photo maskfabrication process for the manufacture of a semiconductor; wet etching;a stripping process; a cleaning or color filter fabrication process; ordeveloping or cleaning in a process for processing a disk such as DVD.

In addition, a gap produced during bubble removal can be changed inaccordance with a diameter of each of the air bubbles or foreign objectsexisting in the chemical solution dispensing port.

While the first to fifth embodiments have described a method forremoving air bubbles in a supplied chemical solution, the sixthembodiment described later describes a method for monitoring particlesincluded in a sucked chemical solution, and terminating a chemicalsolution process according to the number of particles. According to thefifth embodiment, it becomes possible to remove the particles beforedrying a substrate surface. Further, the particles contained in thechemical solution are restricted from adhering to the substrate surface,and the yielding is improved. Note that the particles are by-productscaused at the time of developing (resist residue) or metallic or organicparticles and the like which may exist on the substrate.

Sixth Embodiment

FIG. 12 is a view showing an outline construction of a substrateprocessing section in a substrate developing device according to a sixthembodiment of the present invention. As shown in FIG. 12, the developingdevice comprises: a substrate 110; a substrate holding mechanism forsubstantially horizontally holding a semiconductor wafer, for example; adeveloping unit 120; a cleaning unit 160; and a scan stage 201.

The developing unit 120 comprises: a developing solution dispensing port131; suction ports 132, 133; a pre-wet liquid solution dispensing port134; and a rinse solution dispensing port 135 in a developing solutiondispensing/sucking head 130. A developing solution canister 151 isconnected to the developing solution dispensing port via a pipe 141. Apump 152 is connected to the suction ports 132, 133 via pipes 142, 143.A pre-wet liquid solution canister 153 is connected to the pre-wetliquid solution dispensing port 134 via a pipe 144. A rinse solutioncanister 154 is connected to the rinse solution dispensing port 135 viaa pipe 145. A construction of the developing unit 120 is similar to thatdescribed in Jpn. Pat. Appln. KOKAI Publication No. 2002-252167described previously, and a duplicate description is omitted here.

A construction of the cleaning unit 160 will be described with referenceto FIGS. 12 to 14. FIG. 13 is a view showing a construction of an ozonewater dispensing/sucking head, and FIG. 14 is a plan view when the ozonewater dispensing/sucking head in the developing device is seen from thebottom.

The cleaning unit 160 comprises an ozone water dispensing/sucking head170 which can be scanned on the substrate 110 by the scan stage 201. Theozone water dispensing/sucking head 170 comprises: an ozone waterdispensing port (first dispensing port) 171; first and second suctionports 172, 173; and first and second rinse solution dispensing ports(second and third dispensing ports) 174, 175.

The ozone water dispensing port 171 has an ozone water dispensing outlet(first dispensing outlet) 171 a on a lower face of the ozone waterdispensing/sucking head 170. The first and second rinse solutiondispensing outlet ports 174, 175 have first and second rinse solutiondispensing outlets (second and third dispensing outlets) 174 a, 175 a,respectively, on a lower face of the ozone water dispensing/sucking head170. The first and second suction ports 172, 173 have first and secondsucking inlets 172, 173 a on a lower face of the ozone waterdispensing/sucking head 170.

In the present embodiment, the ozone water dispensing outlet 171 a; thefirst and second rinse solution dispensing outlets 174 a, 175 a; and thefirst and second sucking inlets 172 a, 173 a has long edges in adirection vertical to a scanning direction. These elements are shaped inan elongated port which has short edges in a direction parallel to amoving direction.

An ozone water generator 191 is connected to he ozone water dispensingport 171 via a pipe 181. Particle counter (measuring mechanism, P.C.)192, 193, and a pump 194 are connected to the suction ports 172, 173 viapipes 182, 183. The particle counters 192, 193 measure the number ofparticles by scattering light beams caused by light emission. Rinsesolution canisters 195, 196 are connected to the rinse solutiondispensing ports 174, 175 via pipes 184, 185.

On a side face of the ozone water dispensing/sucking head 170, a capmeasuring mechanism 202 using laser light is provided in order tomeasure a gap between a lower face of the ozone water dispensing/suckinghead 170 and an upper face of the semiconductor wafer 110 placed on asubstrate holder 111.

A moving mechanism has a scan stage 201. A gap adjusting mechanism 203is provided both end parts of the ozone water dispensing/sucking head170. The adjusting mechanism is mounted to be integrated with the ozonewater dispensing/sucking head 170 so as to be movable on the scan stage201 in a vertical direction.

The gap adjusting mechanism 203 comprises a piezoelectric element sothat a gap between the lower face of the ozone water dispensing/suckinghead 170 and the upper face of the semiconductor wafer 110 placed on thesubstrate holder (vacuum chuck) 111 is adjusted to a predetermined valueon the basis of a result of measurement obtained by the gap measuringmechanism 202.

The substrate holding mechanism comprises the substrate holder 111 andan auxiliary plate 112. A substrate 110 is placed on the substrateholder 111. The auxiliary plate 112 is laid out at the periphery of thesubstrate holder 111. The auxiliary plate 112 can move vertically sothat a surface of the substrate 110 is equal to that of the auxiliaryplate 112 in height during developing. In this manner, when thedeveloping solution is sucked by the ozone water dispensing/sucking head170, a sucking force functions equally in a wafer face.

It is preferable to select the auxiliary plate 112 made of a materialsuch that the wetting properties between the substrate of the plate andthat of the substrate become equal to each other. Specifically, acontact angle of the developing solution on the substrate is set so asto be equal to that of the developing solution on the auxiliary plate112.

Now, developing and cleaning processes using the above described deviceswill be described here. The developing solution is supplied into thedeveloping solution dispensing port 131 by pressurizing the developingsolution canister 151. The developing solution is continuously dispensedfrom a developing solution dispensing port 131 a of the developingsolution dispensing port 131 to the substrate 110. When the developingsolution is dispensed, a pre-wet liquid solution is supplied into thepre-wet liquid solution dispensing port 134 by pressurizing the pre-wetliquid solution canister 153. The pre-wet liquid solution iscontinuously dispensed from a dispensing outlet of the pre-wet liquidsolution dispensing port 134 to the substrate 110. A rinse solution issupplied into the rinse solution dispensing port 135 by pressurizing therinse solution canister 154. This rinse solution is continuouslydispensed from a dispensing outlet of the rinse solution dispensing port135 to the substrate 110.

The suction ports 132, 133 suck a solution on a substrate by applying apump sucking force. A mixture liquid solution between the developingsolution and the pre-wet liquid solution is sucked through a suckinginlet of the suction port 132. A mixture liquid solution between thedeveloping solution and the rinse solution is sucked through a suckinginlet of the suction port 133.

As has been described above, while sucking and rinse solution dispensingare carried out at the same time, the port is scanned with a gap ofabout 100 microns being maintained on a photo mask substrate, and adeveloping process is carried out. After the developing process has beencarried out, the head 130 is retracted from the top of the substrate,and an entire face on the photo mask is kept in a state in which therinse solution remains (no dry region).

Now, a cleaning process will be described here. The cleaning process iscarried out while the rinse solution is filled on the photo masksubstrate after developing of a photo resist film has been carried out.

An ozone water is supplied from the ozone water generator 191 into theozone water dispensing port 171. The ozone water is dispensed from theozone water dispensing outlet 171 a of the ozone water dispensing port171 to the substrate. In addition, when the ozone water is dispensed,the rinse solution is supplied into the rinse solution dispensing ports174, 175 by pressurizing the rinse solution canisters 195, 196. Thesolution on the substrate 110 is sucked through the first and secondsuction ports 172, 173 by applying the sucking force of the pump 194.Both of the ozone water and the rinse solution enter the sucking inlet.As described above, while ozone water dispensing, sucking, and rinsesolution dispensing are carried out at the same time, the head 170 isreciprocally scanned on the surface of the photo mask substrate, and thecleaning process is carried out. During reciprocal scanning, a gapbetween the substrate surface and the head lower face is set to about100 microns.

During the cleaning process, the number of particles included in asolution (chemical solution) sucked from the sucking inlet is measuredby means of the particle counters 192, 193. For example, the number ofparticles is measured by using scattering light beams caused by lightemission. A measurement value and measurement position information aretransmitted to a controller 190. The controller 190 compares ameasurement value in a target region R with a predetermined value. Inthe case where the measurement values are greater than the predeterminedvalue in all the target regions on the substrate, the controller 190causes the cleaning process to be continued. In contrast, in the casewhere the measurement values in all the target regions on the substrateare equal to or smaller than the predetermined value, the controller 190causes the scanning and cleaning processes of the head 70 to beterminated at a time point at which the ozone water dispensing/suckinghead reaches an end part of the substrate. Then, the substrate is dried.

In the case of the present embodiment, the number of particles became 0,which excludes the number of microscopic bubbles, in the target region Rat a third reciprocal movement. Thus, the head scanning and cleaningprocesses are interrupted after three and half reciprocal movements, andthen, the substrate was dried. When a defect evaluation was carried outby a mask defect inspecting device with respect to a formed pattern, thenumber of defects was 0 in a pattern area of about 120 mm×120 mm.

It is preferable to count the number of particles by using the particlecounters 192, 193, after the solution sucked through the first andsecond sucking ports 172 a, 173 a has been degassed. Particle countingby the particle counters may count air bubbles contained in a solutionas a noise. In accordance with the methods of the first to fifthembodiments, the number of particles is counted after the microscopicbubbles have been removed from the inside of the liquid solution,thereby making it possible to precisely count the number of particles.

In the present embodiment, the layouts of the chemical solutiondispensing ports and sucking ports are not limited to theabove-described layouts. For example, these ports can be laid out inlocation as shown in FIGS. 15 to 20 and can be laid out in any othersimilar location. In FIGS. 15 to 20, reference numeral 221 denotes afirst chemical solution dispensing port; 222 denotes a first suckingport; 223 denotes a second sucking port; 224 denotes a second chemicalsolution dispensing port; 225 denotes a third chemical solution port;226 denotes a third sucking port 227 denotes a fourth sucking port; 228denotes a third chemical solution dispensing port; 229 denotes a fourthchemical solution dispensing port; 230 denotes a fifth chemical solutiondispensing port; and 231 denotes a sixth chemical solution dispensingport.

In the present embodiment, although the developing solutiondispensing/sucking head and the ozone water dispensing/sucking head arerelatively scanned on a substrate surface, relative scanning is notalways required, depending on the size of the head or the size of thetarget region R. Although the developing solution dispensing/suckinghead and the ozone water dispensing/sucking head has been moved, thesubstrate may be moved. In addition, the substrate and the developingsolution dispensing/sucking head and the ozone water dispensing/suckinghead may be moved.

While the present embodiment has shown an application example relatingto mask developing, the present invention is not limited thereto. Forexample, the present invention can be applied to, for example, a waferdeveloping process or a rinse process; wet etching of an opaque film ona substrate in a photo mask fabrication process for the manufacture of asemiconductor or cleaning of a variety of substrates such as a photomask; and developing in a color filter fabrication process and a processfor processing a disk such as DVD.

FIG. 21 is a view showing an outline construction of adeveloping/cleaning device according to a modified example of the sixthembodiment. Like constituent elements in FIG. 12 are designated by likereference numerals, and a detailed description is omitted here.

As shown in FIG. 21, a chemical solution dispensing port 241 is providedat a developing/cleaning head 240. The developing solution canister 151and the zone water generator 191 are connected to the chemical liquidsolution port 241 via a switching device 242.

In the case of this apparatus, a chemical solution supplied to thechemical solution dispensing port 241 is switched by the switchingdevice 242, whereby a developing process and a cleaning process can becarried out by one head 240.

The following method can also be used to determine the end of thecleaning process according to the number of particles. If the number ofparticles counted at a sucking port at the frontal side in the scanningdirection has become equal to that counted at a sucking port at the rearside in the scanning direction, scanning is terminated at a time pointwhen the nozzle has moved up to the nozzle scanning end position, andthe rinse process is terminated.

When the processing termination is thus determined, incorrect sensing ofparticles due to an effect of the bubbles which exist in the liquid canbe restricted.

The present invention is not limited to the above-described embodiments.For example, while the above embodiments have described the cleaningprocess that follows the developing process, the present invention canbe used for a cleaning process that follows an etching process. Inaddition, an electrolytic ion water or a pure water can be used insteadof the ozone water.

The substrate processing method and the substrate processing apparatusaccording to the sixth embodiment are summarized as follows.

The substrate processing method according to the sixth embodiment isdirected to a substrate processing method for supplying a chemicalsolution to a substrate, and then, processing a target region of thesubstrate by using the chemical solution, the method including:

laying out on a target region a chemical solution dispensing/suckingpart of which a dispensing port for dispensing the chemical solution anda sucking port for sucking a solution on the substrate are laid out on alower face thereof; dispensing the chemical solution from the dispensingport of the chemical solution dispensing/sucking part against thesubstrate; sucking the solution on the substrate at the sucking portduring the dispensing; counting the number of particles included in thesolution sucked through the sucking port during the sucking; and in thecase where a count value of the number of particles included in thesolution sucked in the target region is equal to or smaller than apredetermined value, stopping dispensing of the chemical solution.

During the dispensing, the chemical solution dispensing/sucking part canbe scanned on the substrate surface relatively.

The chemical solution is provided as a developing solution, an ozonewater, an electrolytic ion water, or a pure water.

It is preferable that air bubbles are removed from the chemical solutionsucked through the sucking port.

The substrate processing apparatus according to the sixth embodiment isdirected to a substrate processing apparatus for supplying a chemicalsolution to a substrate, and then, processing a target region of thesubstrate by using the chemical solution, the apparatus comprising: asubstrate holding mechanism which holds a substrate; a chemical solutiondispensing/sucking part which comprises a chemical supply systemincluding a lower face opposed to the substrate and a first chemicalsolution dispensing nozzle which dispenses a first chemical solutionfrom a first chemical solution dispensing port arranged on the lowerface, and a solution sucking system comprising a first sucking nozzlewhich sucks the solution on the substrate from a first sucking portarranged on the lower face; a counting mechanism which counts the numberof particles included in the solution sucked by the solution suckingsystem; and a determining part, in the case where the number ofparticles counted by this counting mechanism is equal to or smaller thana predetermined value, which terminates the chemical solutionprocessing.

The counting mechanism counts the number of particles by the scatteringlight beams caused by light emission.

This apparatus can further comprise a scanning mechanism whichrelatively scans the chemical solution dispensing/suction part on thesubstrate.

The chemical solution supply system further comprises second and thirdchemical solution dispensing nozzles for dispensing second and thirdchemical solutions from second and third chemical solution dispensingoutlets arranged on the lower face, respectively. The solution suckingsystem further comprises a second sucking nozzle for sucking a solutionon the substrate from the second sucking port arranged on the lowerface. The first, second, and third chemical solution dispensing portsand the first and second sucking ports are arranged along the scanningdirection. The first and second sucking ports are arranged so as tosandwich the first chemical solution dispensing port between the suckingports. The second and third chemical solution dispensing ports arearranged so as to sandwich the first and second sucking ports betweenthe dispensing outlets.

The solution sucking system further comprises a second sucking nozzlewhich sucks a solution on the substrate from the second sucking portarranged on the lower face. The first and second sucking ports are laidout so as to sandwich the first chemical solution dispensing portbetween the sucking ports.

The first sucking port is laid out so as to surround the first chemicalsolution dispensing port.

Additional advantages and modifications will readily occur to thoseskilled in the art. Therefore, the invention in its broader aspects isnot limited to the specific details and representative embodiments shownand described herein. Accordingly, various modifications may be madewithout departing from the spirit or scope of the general inventiveconcept as defined by the appended claims and their equivalents.

1. A method of substrate processing, comprising: preparing a substrateprocessing apparatus comprising a substrate holding mechanism to hold atarget substrate to be processed having a first main face, and achemical solution dispensing/sucking mechanism which comprises achemical solution dispensing port to dispense a first chemical solution,and a chemical solution suction port to suck a chemical solutionincluding the first chemical solution; placing the target substrate onthe substrate holding mechanism so as to expose the first main face;preparing an auxiliary plate having a second main face, followed bylaying out the auxiliary plate at a periphery of the target substratesuch that the second main face is substantially flush with the firstmain face; supplying a second chemical solution onto the first main faceand the second main face; dispensing the first chemical solution fromthe chemical solution dispensing port and sucking the first chemicalsolution and the second chemical solution through the chemical solutionsuction port, in a state in which the chemical solution dispensing portand the chemical solution suction port are brought into contact with thesecond chemical solution supplied on the second main face of theauxiliary plate; and while dispensing the first chemical solution fromthe chemical solution dispensing port and sucking the first chemicalsolution through the chemical solution suction port, scanning thechemical solution dispensing/sucking mechanism in a state in which thechemical solution dispensing port and the chemical solution suction portare opposed to the first main face of the target substrate, wherein saiddispensing the first chemical solution from the chemical solutiondispensing port and sucking the first chemical solution and the secondchemical solution through the chemical solution suction port in thestate in which the chemical solution dispensing port and the chemicalsolution suction port are brought into contact with the second chemicalsolution supplied on the second main face of the auxiliary plateincludes dispensing and sucking the first chemical solution in a mannerthat the first chemical solution is precluded from coming into contactwith the first main face of the target substrate.
 2. The methodaccording to claim 1 wherein said scanning the chemical solutiondispensing/sucking mechanism includes reducing a spaced distance betweenthe chemical solution dispensing/sucking mechanism and the first mainface of the target substrate to be shorter than that in said dispensingthe first chemical solution from the chemical solution dispensing portand sucking the first chemical solution and the second chemical solutionthrough the chemical solution suction port.
 3. The method according toclaim 1, further comprising determining whether an air bubble is presentor absent in the chemical solution dispensing port, wherein saidscanning the chemical solution dispensing/sucking mechanism is performedafter it is determined that the air bubble is absent in the chemicalsolution dispensing port.
 4. The method according to claim 3, whereinsaid determining whether an air bubble is present or absent includes,when it is determined that the air bubble is present in the chemicalsolution dispensing port, repeating: said dispensing the first chemicalsolution from the chemical solution dispensing port and sucking thefirst chemical solution and the second chemical solution through thechemical solution suction port in the state in which the chemicalsolution dispensing port and the chemical solution suction port arebrought into contact with the second chemical solution supplied on thesecond main face of the auxiliary plate, and said determining whetherthe air bubble is present or absent in the chemical solution dispensingport, until it is determined that the air bubble is absent in thechemical solution dispensing port.
 5. The method according to claim 1,wherein the chemical solution suction port includes a first chemicalsolution suction port and a second chemical solution suction portprovided so as to sandwich the chemical solution dispensing porttherebetween, and said dispensing the first chemical solution from thechemical solution dispensing port and sucking the first chemicalsolution and the second chemical solution through the chemical solutionsuction port includes making a difference between the first chemicalsolution suction port and the second chemical solution suction port,with respect to a pressure applied to the first chemical solution andthe second chemical solution for said sucking.
 6. The method accordingto claim 1, wherein said dispensing the first chemical solution from thechemical solution dispensing port and sucking the first chemicalsolution and the second chemical solution through the chemical solutionsuction port includes vibrating one selected from the group consistingof (1) the chemical solution dispensing/sucking mechanism, (2) the firstchemical solution and the second chemical solution, and (3) the chemicalsolution dispensing mechanism, the first chemical solution and thesecond chemical solution.
 7. The method according to claim 1, whereinsaid sucking the first chemical solution and the second chemicalsolution through the chemical solution suction port includes countingthe number of particles included in the first chemical solution and thesecond chemical solution sucked through the chemical solution suctionport, followed by, in a case where the number of the particles is equalto or smaller than a predetermined value, stopping said dispensing thefirst chemical solution.
 8. A method of manufacturing a semiconductordevice comprising: preparing a substrate processing apparatus comprisinga semiconductor wafer holding mechanism to hold a target semiconductorwafer to be processed having a first main face and a chemical solutiondispensing/sucking mechanism including a chemical solution dispensingport to dispense a first chemical solution and a chemical solutionsuction port to suck a chemical solution including the first chemicalsolution; placing the target semiconductor wafer on the semiconductorwafer holding mechanism so as to expose the first main face; preparingan auxiliary plate having a second main face, followed by laying out theauxiliary plate at the periphery of the target semiconductor wafer suchthat the second main face is substantially flush with the first mainface; supplying a second chemical solution onto the first main face andthe second main face; dispensing the first chemical solution from thechemical solution dispensing port and sucking the first chemicalsolution and the second chemical solution through the chemical solutionsuction port, in a state in which the chemical solution dispensing portand the chemical solution suction port are brought into contact with thesecond chemical solution supplied on the second main face of theauxiliary plate, in a manner that the first chemical solution isprecluded from coming into contact with the first main face of thetarget semiconductor wafer; and while dispensing the first chemicalsolution from the chemical solution dispensing port and sucking thefirst chemical solution through the chemical solution suction port,scanning the chemical solution dispensing/sucking mechanism in a statein which the chemical solution dispensing port and the chemical solutionsuction port are opposed to the first main face of the targetsemiconductor wafer.
 9. The method according to claim 8, wherein saidscanning the chemical solution dispensing/sucking mechanism includesreducing a spaced distance between the chemical solutiondispensing/sucking mechanism and the first main face of the targetsemiconductor wafer to be shorter than that in said dispensing the firstchemical solution from the chemical solution dispensing port and suckingthe first chemical solution and the second chemical solution through thechemical solution suction port.
 10. The method according to claim 8,further comprising determining whether an air bubble is present orabsent in the chemical solution dispensing port, wherein said scanningthe chemical solution dispensing/sucking mechanism is performed after itis determined that the air bubble is absent in the chemical solutiondispensing port.
 11. The method according to claim 10, wherein saiddetermining whether an air bubble is present or absent includes, in thecase where it is determined that an air bubble is present in thechemical solution dispensing port, repeating: said dispensing the firstchemical solution from the chemical solution dispensing port and suckingthe first chemical solution and the second chemical solution through thechemical solution suction port in the state in which the chemicalsolution dispensing port and the chemical solution suction port arebrought into contact with the second chemical solution supplied on thesecond main face of the auxiliary plate, and said determining whetherthe air bubble is present or absent in the chemical solution dispensingport, until it is determined that the air bubble is absent in thechemical solution dispensing port.
 12. The method according to claim 8,wherein the chemical solution suction port includes a first chemicalsolution suction port and a second chemical solution suction portprovided so as to sandwich the chemical solution dispensing porttherebetween, and said dispensing the first chemical solution from thechemical solution dispensing port and sucking the first chemicalsolution and the second chemical solution through the chemical solutionsuction port includes one selected from the group consisting of (1)making a difference between the first chemical solution suction port andthe second chemical solution suction port, with respect to a pressureapplied to the first chemical solution and the second chemical solutionfor said sucking; (2) sucking the first chemical solution and the secondchemical solution on the target semiconductor wafer through at least oneof the first chemical solution suction port and the second chemicalsolution suction port; (3) vibrating the chemical solutiondispensing/sucking mechanism; (4) vibrating the first chemical solutionand the second chemical solution; and (5) vibrating the chemicalsolution dispensing/sucking mechanism, the first chemical solution andthe second chemical solution.